DEVICE FOR SPREADING BITUMINOUS MIX FROM A FILM OF DETERMINED THICKNESS OF THE MIX, IMPLEMENTATION METHOD

Abstract

The device comprises means for moving on said ground along a longitudinal direction of advancement (32) and spreading means supplied with bituminous asphalt by feeding means and adapted to spread, during the movement of the device, the layer of bituminous asphalt over a determined width of said ground considered transversely to the direction of advancement. The spreading means are adapted to perform the rolling, crumbling, and settling of the bituminous asphalt onto the ground.

Description

[0001] The present invention relates to a device for spreading a bituminous coating in a thin layer, called a film, as well as a method for implementing this device. It has applications in the field of public works, particularly in the construction of roads or, especially advantageously, in their maintenance or renovation.

[0002] Asphalt (or bituminous asphalt) is a mixture of gravel, sand, and a hydrocarbon binder (commonly called bitumen) applied in one or more layers to form the road surface. Traditionally, the application of an asphalt layer can be carried out in various ways. These include hot mix asphalt (temperatures above 130°C), warm mix asphalt (temperatures between 100°C and 130°C), semi-warm mix asphalt (temperatures between 85°C and 100°C), cold mix asphalt, cold mix asphalt, and emulsion-treated aggregates, all of which, for the purposes of this document, are referred to as "asphalt mixes."

[0003] Currently, asphalt paving is carried out by leveling the layer directly on the substrate, which is generally the ground or an existing asphalt sub-base. Leveling is done using either a screed, such as a paver screed or a rapid intervention paver (FIR), or a grader blade. These methods depend on the quality of the substrate receiving the layer. This substrate quality is characterized by the presence of varying degrees of longitudinal and transverse deformations, bulges, and different surface textures, such as smooth, very rough, rich, or lean.These heterogeneities do not allow for good control of the dosage or proper smoothing of the asphalt laid to form the layer, and this is all the more impactful when the deformations are significant or the implementation thicknesses are small, especially when the layer thickness is less than 3 cm.

[0004] Traditional methods of spreading asphalt on the ground involve self-propelled machines, known as pavers, which have, at the rear relative to their direction of travel, a means for depositing and distributing the asphalt across the ground widthwise. Further back, a smoothing screed is used to create a level surface layer. Vibrators are also employed to facilitate distribution and compact the layer. Optionally, a spray bar for applying a tack coat and / or waterproofing layer can be installed in front of the asphalt paver. An asphalt tank is mounted at the front of the machine and can be continuously supplied by a truck whose asphalt tipper empties into the tank.A conveyor line transports the asphalt mix from the tank at the front to the rear of the machine, where it is deposited on the ground. The machine is equipped with tracks or tires for ground movement and with control systems for its movements and various components. In particular, control systems allow for a degree of automation and regulation in the application of the asphalt layer.

[0005] With this method, the bituminous asphalt is laid directly onto the ground and then leveled to form a layer of a specific width and thickness. The layer's height, and therefore its thickness, depends on the machine's height, the angle of attack, and the screed. The screed is attached to the self-propelled machine and thus follows its movements, particularly any unwanted movements caused by ground surface deformations. These unwanted movements can vary in magnitude depending on the ground deformations over which the machine is moving, and can even be amplified by the leverage between the machine and the screed. To minimize the resulting surface irregularities, methods can be used to correct these unwanted movements caused by ground deformations.However, since the smoothing table is a rigid bar, it is not possible to correct all the effects of these untimely movements.

[0006] Another disadvantage of this method is that it is not possible to obtain a thin layer because if the smoothing table is lowered too far, the distribution of the asphalt on the ground may be degraded, for example with the risk of tearing off the bituminous asphalt, or in the event of deformation of the ground under the machine or under the leveling blade, of friction of the leveling blade on the ground.

[0007] Finally, with this method, the amount of asphalt in the layer at any point on the ground cannot be precisely controlled. Indeed, if there is a depression in the ground, the asphalt fills it up to the level of the layer's surface, which is practically at the same absolute height as all around the depression. Therefore, there will be more asphalt directly above such a depression than elsewhere. The opposite will be true at a bump in the ground, with less asphalt, not to mention the risk that the trowel might hit the bump if a thin layer is attempted.

[0008] This method should therefore preferably be implemented after sufficient soil preparation, particularly leveling. Furthermore, it results in relatively thick layers, making precise control of the amount of asphalt spread per unit area practically impossible.

[0009] The present invention aims to overcome these drawbacks by using a spreading method with a spreading device in which the bituminous mixture is metered before being deposited on the ground. This method deposits a predetermined quantity of bituminous mixture onto the ground. The resulting layer contains a constant, predetermined quantity of bituminous mixture at every point on its surface, regardless of any deformations in the ground surface on which the layer is spread. This makes it possible to create a very thin layer, which is particularly advantageous for road resurfacing or on suitable substrates.

[0010] We will see that it is possible to use two methods to achieve this application rate: either by laying a bituminous asphalt film of a predetermined thickness between two rollers, or by laying a bituminous asphalt film of a predetermined thickness on an endless conveyor belt. In both cases, the bituminous asphalt film is then crumbled and falls, notably by being projected, onto the ground. In the first case, the film created can be considered to crumble almost immediately since the same rollers are responsible for both laying the film (controlling the quantity of material) and then crumbling it. In the second case, the film has a longer physical lifespan because one of the rollers is a roller laid out as an endless conveyor belt.

[0011] Document DE2125970 describes a device comprising pairs of parallel rollers between which a film of asphalt is laid for spreading on the ground. This device allows for even spreading but does not include a means of final crumbling for projection of the asphalt onto the ground.

[0012] Thus, the invention relates to a device for spreading a layer of bituminous coating on a ground to be covered, comprising means for moving on said ground in a longitudinal direction of advancement and spreading means supplied with bituminous coating by supply means and adapted to spread during the movement of the device the layer of bituminous coating over a determined width of said ground considered transversely to the direction of advancement.

[0013] According to the invention, the spreading means are adapted to achieve above ground a rolling of the bituminous coating and a crumbling of the rolled bituminous coating and the fall towards the ground of the crumbled bituminous coating.

[0014] In various embodiments of the invention, the following means, which may be used alone or in any technically possible combination, are employed: The rolling of the bituminous asphalt is carried out over a determined transverse length; the device includes a distributor adapted to spread the bituminous asphalt at the inlet of the spreading means; the spreading means are adapted to project the crumbled bituminous asphalt onto the ground; the spreading means include at least one rolling / crumbling sub-assembly maintained at a determined height above the ground and consisting of two rough cylinders, both arranged in the same transverse direction, such that the cylinders form a film of bituminous asphalt between them with a determined thickness corresponding to the determined distance between the generatrices opposite the two cylinders, the two cylinders being substantially of equal length.The two cylinders rotate in opposite directions to each other in order to drive between them bituminous asphalt introduced from one side of the inlet of the rolling and crumbling sub-assembly. The rough cylinders have raised patterns on their surfaces to drive the bituminous asphalt, causing, on the outlet side of the rolling and crumbling sub-assembly, a crumbling of the rolled film of bituminous asphalt passing between the two cylinders, as well as the fall of the crumbled asphalt to the ground. The two rough cylinders rotate, in absolute value, at the same radial speed. The spreading means comprise at least one rolling and crumbling sub-assembly consisting of an extended roller and a rough cylinder, and the extended roller is formed by an end portion of an endless conveyor belt extended between an upstream inner roller and a downstream inner roller, the upstream and downstream inner rollers being parallel. to the rough cylinder,with the downstream inner roller opposite the cylinder, the conveyor belt having a width substantially equal to the length of the cylinder, a film of determined thickness of bituminous coating being made on the upper surface of the conveyor belt by a grader arranged on the upstream side of said conveyor belt, said film being carried towards the cylinder by said conveyor belt and the cylinder rotating, in absolute value, at a speed greater than the radial speed of the conveyor belt passing over the downstream inner roller,the determined distance between the surfaces of the cylinder and the conveyor belt passing over the downstream inner roller being less than the determined thickness of the bituminous asphalt film produced on the upper surface of the belt; the grader comprises a transverse leveling wall whose lower end is substantially parallel to the upper surface of the belt and whose lower end is at a determined adjustable height from the upper surface of the belt; the section of belt disposed between the leveling wall and the downstream inner roller is equipped with a weighing belt system which makes it possible to measure the mass of the asphalt strand passing over the belt at the level of said weighing belt system; the distributor is disposed transversely above the belt and upstream of the leveling wall,The spreader is adapted to spread the bituminous asphalt upstream of the leveling wall over a determined width of the conveyor belt and over a height greater than the determined thickness of the bituminous asphalt film to be produced; the spreader includes, in a cage, a worm screw for driving the bituminous asphalt over the width of the conveyor belt,The cage, enclosed by side walls and bottomless to allow the bituminous mix to spread over the upper surface of the conveyor, is open at the top for feeding with bituminous mix. The leveling wall is independent of the distributor cage. The distributor cage is at a fixed height. The distributor cage is at an adjustable height. The height of the auger in the cage is fixed. The height of the auger in the cage is adjustable. The adjustment of the height of the lower end of the leveling wall is independent of the adjustment of the height of the distributor cage. The adjustment is a manual mechanical adjustment. The manual mechanical adjustment is chosen from at least the following means: screw, bolt, shim, notch, rack, or jaw adjustment. The adjustment is ensured by a controlled position actuator. The controlled position actuator is chosen from among the electrical actuators.pneumatic, hydraulic; the leveling wall constitutes the downstream side wall of the distributor cage, the distributor cage being located at a predetermined adjustable height from the upper surface of the conveyor; the height of the auger in the cage is adjustable so that the height of the auger relative to the upper surface of the conveyor can be adjusted regardless of the height of the cage relative to the upper surface of the conveyor,particularly in the case where the downstream side wall of the spreader cage is the leveling wall and the cage is height-adjustable to regulate the height of the lower end of the leveling wall; the device comprises four rolling and crumbling sub-assemblies, each consisting of a patterned cylinder and an extended roller; the device comprises three rolling and crumbling sub-assemblies, each consisting of a patterned cylinder and an extended roller; the device comprises two rolling and crumbling sub-assemblies, each consisting of a patterned cylinder and an extended roller; in the case of a device comprising at least two rolling and crumbling sub-assemblies, each consisting of a patterned cylinder and an extended roller, the sub-assemblies are arranged laterally offset from each other in order to add the spreading widths of each sub-assembly over a larger total ground width,the spreading being continuous across the width of the ground, i.e. without gaps or overlaps; in the case of a device comprising at least two laterally offset flaking / crumbling sub-assemblies, the lateral offset between the sub-assemblies is adjustable in order to select the total spreading width, the spreading being continuous across the width of the ground, i.e. without gaps or overlaps; the device comprises a frame supporting two flaking / crumbling sub-assemblies, each consisting of a patterned cylinder and an extended roller, the two sub-assemblies being offset, on the one hand, laterally from each other and, on the other hand, vertically from each other,The two rolling and crumbling sub-assemblies are movable laterally against the support frame so as to allow the two sub-assemblies to be moved apart or brought together in overlapping positions along a lateral direction parallel to the width of the road, thus increasing or decreasing the determined width of the ground on which the bituminous mixture is spread. The device comprises one distributor per rolling and crumbling sub-assembly, the two distributors of the two sub-assemblies transporting the bituminous mixture in two opposite and diverging directions over the width of each endless conveyor belt. The distributor is supplied with bituminous mixture by a chute in a fixed position above the distributor cage, and the two chutes for the two rolling and crumbling sub-assemblies are arranged against the median axis of the device, superimposed on the direction of travel. The device forms a self-propelled spreading machine.said spreading means being arranged at the rear of said machine, or being installed in a removable manner at the rear of a self-propelled machine, said self-propelled machine comprising, from front / upstream to rear / downstream according to the direction of travel: a reservoir of bituminous mix, at least one conveying line for the bituminous mix towards the rear and said spreading means; the device comprises at least two rolling / crumbling sub-assemblies and one conveying line for the bituminous mix per sub-assembly, each conveying line being controllable independently of the other conveying line(s), the embossed patterns are substantially elongated along the length of the cylinder, the embossed patterns are essentially threadlike and of a height between 1 mm and 15 mm.

[0015] The invention also relates to a method for spreading a layer of bituminous coating on a ground to be covered, in which, in the first stage, the bituminous coating is rolled to create a film of determined thickness of bituminous coating over a determined width and at a distance above the ground and, in the second stage, said film is crumbled and the bituminous coating from the crumbled film is dropped onto the ground.

[0016] In a particular mode of said process, the film of determined thickness of bituminous coating is made on an upstream part of an extended roller consisting of an endless conveyor belt extended between an upstream inner roller and a downstream inner roller, and a cylinder having raised patterns is used opposite the downstream inner roller to crumble the film made on the endless belt.

[0017] In certain specific modalities of the process, a bituminous mix is ​​used, chosen from: a hot mix with a manufacturing temperature above 150°C, a warm mix with a manufacturing temperature above 100°C and below 150°C, a semi-warm mix with a manufacturing temperature between 85°C and 100°C, a semi-cold or cold mix with a manufacturing temperature below 85°C.

[0018] In certain specific modalities of the process, a bituminous coating is used whose d and D values ​​of the d / D ratio are chosen from: a value of 0-2-4 or 6.3 mm for d and a value of 4-6.3-10-14-20 mm for D.

[0019] The present invention will now be exemplified, without being limited to it, by the following description in relation to the following figures: there Figure 1 which represents a simplified functional diagram of means for spreading bituminous asphalt in the extended roller embodiment consisting of an endless conveyor belt extending between an upstream inner roller and a downstream inner roller, the Figure 2 which represents an oblique front view and perspective of a paving machine equipped at the rear with two means of spreading bituminous asphalt according to the extended roller embodiment, the Figure 3 which represents an oblique rear view and perspective of the paving machine Figure 2 equipped with its two extended roller-type bituminous asphalt spreading systems, the Figure 4 which represents a rear side and perspective view of one side of the paving machine equipped with the Figure 2 , there Figure 5 which represents a rear side and perspective view of a second side of the paving machine equipped with the Figure 2 , there Figure 6 which represents a close-up side view centered on the screw distributor of the first of the bituminous asphalt spreading means located on the first lateral side of the paving machine equipped with the Figure 2 , there Figure 7 which represents a close-up side view centered on the downstream inner drive roller of the endless conveyor and on the corresponding patterned cylinder of the second of the bituminous asphalt spreading means located on the second lateral side of the paving machine equipped with the Figure 2 , there Figure 8 which represents a close-up rear view of the paving machine equipped with the Figure 2 , there Figure 9 which represents a rear side perspective view of the paving machine equipped with the Figure 2 during operation with projection and fall to the ground of crumbled bituminous asphalt, the Figure 10 which represents a schematic cross-section of spreading means with two rough cylinders, and the Figure 11 which schematically represents a trailer towed by means for spreading bituminous coating according to the invention and which includes in particular three wheels which are cylinders with smooth rims and means for storing water and a bonding / sealing emulsion as well as means for using these products.

[0020] In its general principle, the invention is characterized in that the spreading of the bituminous mixture is carried out by rolling means that condition the mixture into a film of controlled thickness and width before being crumbled and falling onto the ground, preferably by being projected onto it. The creation of the film is referred to as rolling, and the film is obtained by passing the bituminous mixture between two elements that move relative to each other, in particular two rotating cylinders, or between a fixed element relative to a moving element, in particular a leveling wall relative to an endless conveyor belt of an extended cylinder.

[0021] When using two rollers, the bituminous asphalt film of a predetermined thickness is laid between the two rollers, preferably rotating at the same absolute radial speed to facilitate precise metering. While the two rollers ideally rotate in opposite directions, the scenario where they rotate in the same direction is also considered, particularly when one roller rotates faster than the other to apply the bituminous asphalt to the ground. Therefore, different absolute radial speeds for the two rollers are possible, but this can, under certain conditions, complicate the theoretical estimation of the film's material quantity due to potentially non-linear effects. In such cases, measurements taken on an operating machine can, if desired, allow for the creation of metering curves based on the machine's settings.Indeed, under certain conditions, during tests, a lack of linearity in dosing with the radial speed of the roller(s) and also with the spacing between the rollers was observed.

[0022] In the case of the implementation of an extended cylinder, the movement of an endless conveyor belt is combined with successive functions of supplying bituminous asphalt, transverse distribution of the bituminous asphalt on the endless conveyor belt, creation on the endless conveyor belt of a film of bituminous asphalt having a determined thickness, crumbling of the film and spreading by falling, and preferably projection, of the crumbled film on the ground.

[0023] The ground on which the layer is spread is preferably prepared to receive said layer of bituminous asphalt. A tack coat and / or waterproofing layer may be applied to the ground before spreading the bituminous asphalt or simultaneously during the spreading process.

[0024] In this description, the terms front and rear are defined with respect to the direction of travel on the ground of the spreading means, with the spreading means moving forward. The terms upstream and downstream are defined with respect to the direction of flow of the asphalt mix within the spreading means, with the spreading occurring downstream to form a layer of asphalt mix on the ground, the asphalt mix entering the spreading means from upstream.

[0025] In the spreading machine that will be described in more detail, the rear and downstream sides correspond, as the spreading takes place at the rear, while the upstream side faces forward. Furthermore, the spreading equipment is positioned towards the rear of the machine. However, other configurations are possible, such as a spreading machine in which the downstream side of the assembly faces forward and / or the spreading equipment is positioned at the front. The machine could also be a roller.

[0026] Thanks to the invention, the asphalt mix is ​​applied uniformly and continuously regardless of ground deformation, provided the ground is accessible to construction equipment, particularly the spreading machine implementing the invention. The invention allows for controlled application of the asphalt mix over a range from 6 kg / m² to at least 50 kg / m².

[0027] Furthermore, since the invention is applicable to all types of asphalt mixes: hot mix, warm mix, semi-warm mix, semi-cold mix, cold mix emulsion-type aggregate, cold open mix, and cold dense mix, it is possible to adapt the asphalt mix formulation to the specific characteristics of the paving site. This adaptation can be made based on the desired asphalt layer thickness, the characteristics of the subgrade, and in particular the level of deflection and / or the traffic intensity.

[0028] For example, for thin-layer applications with application rates between 6 kg / m² and less than 30 kg / m², a continuous or discontinuous formulation with a high modulus of content can be used: a binder content greater than 5.4% and a content of particles smaller than 63 µm preferably greater than 6%, using a bitumen grade selected from 50 / 70, 70 / 100, 160 / 220, 250 / 330, 330 / 430, 500 / 650, 650 / 900, or modified bitumens. Modified bitumens are preferably used for heavily trafficked roads or roads whose geometric configuration, particularly winding and / or sloping ones, generates high stresses.

[0029] For thicker layer applications, in a range of 30 to 60 kg / m², the asphalt mix can be formulated in accordance with applicable regulations or standards. For emulsion-based aggregates, in accordance with standard NF 98-121. For ultra-thin bituminous concrete (BBUM) with an average dosage of 30 kg / m², in accordance with standard NF EN 13109-9. For very thin bituminous concrete (BBTM) with an average dosage of 60 kg / m², in accordance with standard NF EN 13108-2. For thin bituminous concrete (BBM) with an average dosage of 90 kg / m², i.e., a nominal thickness of 4 cm, in accordance with standard NF EN 13108-1. For very thin bituminous concrete (BBF), in accordance with standard NF EN 98-139. For BBDr (Draining Bituminous Concretes).

[0030] The invention can be applied to bituminous mixes with a (D) of 4 mm, 6.3 mm, 10 mm, or 14 mm and a (d) of the bituminous mix equal to 0 mm, 2 mm, 4 mm, or 6.3 mm. It should be noted that the granular class, denoted d / D, with d <D, désigne un intervalle de dimensions de particules en termes de dimension inférieure (d) et supérieure (D) de tamis, exprimées en mm. Les moyens de production classiques d'enrobés bitumineux peuvent être utilisés dans le cadre de l'invention, notamment centrale d'enrobage à chaud ou centrale d'enrobage à froid.

[0031] In the following description, the endless conveyor embodiment, that is, the application of spreading means comprising a patterned cylinder and an extended roller, will be described in greater detail. This is because the film of a specific thickness produced in this device has a longer lifespan and greater spread than the two-patterned-cylinder rolling-crumbling sub-assembly, thus simplifying the explanation. Indeed, in the two-patterned-cylinder sub-assembly, the bituminous asphalt film produced between the patterned cylinders is almost immediately crumbled because the film formation and crumbling zones are very close together. Using an endless conveyor means employing a cylinder in an extended form, making it possible to further separate the bituminous asphalt film formation zone from the crumbling zone.

[0032] In an equivalent variant to the first method with a two-patterned roller sub-assembly, two extended rollers can be used, each consisting of two endless, patterned conveyors facing each other and rotating in the same direction for the sections of the conveyors opposite each other, preferably with the same absolute radial speed. In such a case, it is understood that this allows the film formation zone (upstream, inlet side of the two extended patterned rollers) to be separated from the crumbling zone (downstream, outlet side of the two extended patterned rollers). The adjustable gap between the two opposing endless conveyors allows the thickness of the asphalt film to be regulated, and therefore the application rate, and thus the quantity, of asphalt spread on the ground.The constraint of the bituminous coating film between the two endless belts of two extended patterned cylinders allows for a vertical, inclined or horizontal arrangement of the two endless patterned belts.

[0033] The endless conveyor belt and its combined functional components are integrated and supported by a self-propelled tractor that provides controlled-speed propulsion and supplies the energy and fluids necessary for the proper operation of the spreading device. This machine is generally a paver or a paver tractor, which provides movement as well as supplying asphalt, energy, and fluids. The spreading device is then installed in place of the paver's screed. In the first case, a custom-built machine is used, and in the second, a standard paver is used, with the spreading device mounted on the tractor to replace the traditional spreading tool.In yet another variant, the device of the invention is a trailer that can be towed by a self-propelled vehicle, for example a bituminous asphalt delivery truck, a quick coupling means being implemented between the two.

[0034] On the functional diagram of the Figure 1 representing a sub-assembly 1 with a cylinder 12 with raised patterns 13 and an extended roller consisting of an endless conveyor belt 8 between an upstream inner roller 10 and a downstream inner roller 9, the bulk bituminous mix arrives on the upstream / inlet side of the assembly, which has been represented by a wide curved arrow 11 on the left of the Figure 1 and this corresponds to a bituminous asphalt supply function. The bituminous asphalt arriving on the endless conveyor belt on the upstream side is spread transversely / laterally across the width of the belt 8 by a distributor 7, which performs the transverse distribution function of the bituminous asphalt on the belt 8. The upper surface of the belt 8, which receives the bituminous asphalt, moves from upstream to downstream. In this functional diagram, the distributor 7 also acts as a leveler to form a film 6 of a determined thickness of bituminous asphalt on the belt 8. On the Figure 1 We have omitted to represent certain areas of film 6 in order to show the conveyor belt 8 which supports film 6, and in fact, the bituminous asphalt film 6, conveyed downstream by conveyor belt 8, is continuous at the outlet of the distributor 7, which also functions as a grader. This film 6 is broken up on the downstream / output side of the assembly by a cylinder 12 with raised patterns 13, positioned opposite the downstream inner roller 9. On the Figure 1 The patterned cylinder 12 13 is exaggeratedly separated from the conveyor belt 8 carried by the downstream inner roller 9 to better illustrate the crumbled bituminous asphalt 5 falling and projected onto the ground 2. In practice, the gap between the two is less than the thickness e of the film 6 so that the raised patterns 13 of the cylinder can effectively carry and crumble the bituminous asphalt from the film 6. These raised patterns 13 of the cylinder 12 are preferably substantially elongated along the length of the cylinder: paddles, chevrons, etc. In a variant, they are "bristles" or brush-type spikes, but they then have a smaller effective carrying surface than patterns elongated along the length of the cylinder.

[0035] The crumbled bituminous asphalt falling onto the ground 2 then forms a layer 4 of bituminous asphalt, which is subsequently rolled over. On the Figure 1 We have schematically represented the prior application of a sealing and bonding layer 3 before the spreading of the crumbled bituminous coating 5. The assembly, which is above the ground 2, moves in the direction indicated by the arrow 32. We understand therefore that with the bituminous coating film carried and transported by the conveyor belt 8, we create the equivalent of the layer 4 which is formed on the ground, the dosage on the ground however depending on the speed of advancement of the assembly on the ground as will be specified later.

[0036] The conveyor belt 8 consists of a high-temperature resistant rubber belt, at least up to 180°C, or any other means that allows it to support the asphalt mix and convey it at a linear speed of between 2 meters per minute and 20 meters per minute. The conveyor belt, which is substantially horizontal, is supported by two internal rollers: an upstream internal roller 10 on the incoming side of the asphalt mix and a downstream internal roller 9 on the crumbling side of the asphalt film. One of the internal rollers of the endless conveyor belt is driven to ensure its rotation. Preferably, it is the downstream internal roller 9 that is driven to maintain tension on the conveyor belt carrying the asphalt film. The drive is preferably a hydraulic motor.

[0037] The spacing between the inner rollers 10 and 9 provides an effective length of the endless conveyor 8 of at least 1 m. This effective length corresponds to the upper surface of the endless conveyor 8 on which the bituminous asphalt film 6 is laid and conveyed. Furthermore, between the inner rollers 10 and 9, at least the upper part of the endless conveyor slides on a rigid plate to prevent it from deforming under the weight of the bituminous asphalt film and thus maintain a film of constant thickness.

[0038] The function of supplying 11 with bituminous mixes for the distributor 7 located above the endless conveyor belt 8 is ensured by a conveyor or any other device which makes it possible to ensure a flow rate of bituminous mixes of between 10 tonnes per hour and 100 tonnes per hour.

[0039] We will now describe, starting with the Figure 2 The implementation of the bituminous asphalt spreading device on a paving tractor 14 as a replacement for a conventional paving screed. The device is installed on a removable module 33 which can be connected to the rear of the paving tractor 14 in place of the paving screed. The device is divided into two sub-assemblies, each consisting of a patterned cylinder 12 and an extended roller of the endless belt type 8.

[0040] On the Figure 2 The paving tractor 14 has a front-mounted buffer tank 35 for asphalt mix, which can be opened laterally to continuously supply asphalt mix to the rear of the truck. Protective devices 29 at the front of the tractor allow the asphalt mix truck to be pushed forward as the paving tractor advances, moving along the ground on tracks 28. An engine and drive unit is located behind the buffer tank 35. A conveyor, not visible but indicated by reference number 30 with a dashed arrow, draws asphalt mix from the bottom of the buffer tank 35 and sends it to the rear of the paving tractor, passing between the tracks 28 and under the engine and drive unit.This conveyor 30 is here double, with two parallel lanes that can be controlled independently of each other according to the bituminous coating requirements of each sub-assembly 1a, 1b with patterned cylinder 12 13 and extended roller 8, 9, 10.

[0041] On the Figure 3 We can see more precisely the removable module 33 with its two sub-assemblies 1a and 1b, each with cylinders 12 featuring a raised pattern 13 and extended rollers, each consisting of an endless belt 8 between an upstream inner roller 10 and a downstream inner roller 9. The two sub-assemblies 1a and 1b are offset both laterally and vertically. The lateral offset between the two sub-assemblies 1a and 1b is adjustable to allow for a wider or narrower layer of bituminous asphalt on the ground. The two sub-assemblies 1a and 1b can therefore overlap to varying degrees, hence the need for the vertical offset so that one 1b can pass under the other 1a.

[0042] The removable module 33 comprises a rigid support frame 16 fixed to the paver, the inclination and / or height of which relative to the paver can be adjusted by means of controlled cylinders. A walkway is fixed to the upper part of the support frame 16 to allow personnel access to the operator's station and to observe the operation of the two sub-assemblies, or even to adjust certain components accessible from the walkway.

[0043] The two subassemblies 1a and 1b are supported laterally by the support frame 16 via bearings 17 towards the rear / downstream of the subassemblies and 17' towards the front / upstream of the subassemblies. Note that assembly 1a, which is the higher one, also supports assembly 1b, which is the lower one, by sliding it towards the rear / downstream. This can be seen more precisely on the Figure 7 , one of the embodiments of the rolling elements 17 for sub-assembly 1 b.

[0044] The patterned cylinder 12 with 13 is driven in rotation by a hydraulic motor 26, and the downstream inner roller 9 by a hydraulic motor 25, which is more clearly visible in assembly 1a since these motors are on the observer's side. A belt scraper 34 is positioned towards the bottom of the downstream inner roller 9 to scrape the upper / outer surface of the belt 8 and remove any bituminous asphalt that may have remained stuck to the belt after it has passed under the patterned cylinder 12 with 13.

[0045] Side of subset 1b, which is the most visible on the Figure 3 , we can see upstream of the endless conveyor 8, the leveling wall 22 of the grader which is behind / downstream of the cage 15 of the distributor 7.

[0046] The transverse distribution function of the distributor is ensured by a worm screw, visible on the Figures 5 And 6for each sub-assembly 1a, 1b, positioned in a cage 15 open at the top to receive the asphalt coming from a ramp 21 and the conveyor 30 and open at the bottom to distribute the asphalt transversely on the belt 8.

[0047] To ensure the even distribution of the asphalt mix by the auger onto the conveyor belt, this transverse distribution is carried out in cage 15 across the width of the belt, creating a channel whose thickness is preferably at least four times the (D) of the asphalt mix. For example, with 0 / 10 asphalt, the channel under the auger should preferably have a minimum thickness of 40 mm.

[0048] In practice, the bituminous mix, characterized by its d / D ratio, can be chosen with a value of 0, 2, 4, or 6.3 mm for (d) and a value of 4, 6, 3, 10, 14, or 20 mm for (D). Similarly, the bituminous mix can be chosen from hot mix asphalt with a manufacturing temperature above 150°C, warm mix asphalt with a manufacturing temperature above 100°C and below 150°C, semi-warm mix asphalt with a manufacturing temperature between 85°C and 100°C, and semi-cold or cold mix asphalt with a manufacturing temperature below 85°C.

[0049] As seen on the Figure 4 For assembly 1a, a spray bar 19 for a sealant and / or bonding agent is positioned upstream / in front of the sub-assemblies. This spray bar is supplied with the bonding / sealing emulsion by devices that will be described in relation to the trailer of the figure 11 These components include an emulsion tank and an emulsion pump. The spray booms follow the lateral movements of the sub-assemblies when adjusting the spreading width. Preferably, during the initial setup, a tack coat is first sprayed onto the ground in front of the drop zone using the spray boom, followed by the application of the crumbled bituminous asphalt.

[0050] Note the presence of a level sensor 18 on the lateral end of the cage 15 of the auger distributor 7 of assembly 1a. This level sensor 18 is located on the lateral side of the cage 15, that is, opposite the point on the cage 15 where the bituminous mixture arrives via the feed function 11, the upper end of the feed ramp 21 of which can be seen. The auger rotates to send and distribute the bituminous mixture in a stream towards the lateral end of the cage 15. This sensor 18 allows the bituminous mixture supply 11 to be cut off when there is sufficient bituminous mixture in the cage and it has reached the lateral side of the cage. This prevents the bituminous coating from overflowing out of the cage while ensuring proper distribution of the coating on the surface of the endless conveyor belt 8 and in order to obtain a uniform film.

[0051] The two feed ramps 21 of the two subassemblies receive the bituminous mix arriving via the double conveyor 30 located between the tracks 28 of the tractor 14. These two feed ramps 21 allow the bituminous mix to be raised above the two cages 15 of the two subassemblies 1a, 1b. The two feed ramps are in fixed positions and are arranged on either side of the central axis of the tractor and the module 33, essentially one against the other. It is therefore understood that the bituminous mix will fall into the cage at a point that will depend on the lateral position of the assembly 1a, 1b. When each subset 1a, 1b is pushed totally outwards to obtain maximum layer width, the place where the bituminous coating falls into the cage is the central end, i.e. towards the median axis, of the cage 15 and the film is therefore made over the whole width of the endless belt 8.

[0052] However, when the subassemblies are brought together and overlap to create a narrower layer, the point where the bituminous mix falls into the cage is an intermediate position between the two ends, lateral and central, of the cage 15. Because the auger distributes the mix towards the lateral side, the film will only be formed over a reduced width of the endless conveyor belt and its lateral side. Thanks to this, there is no overlapping of the spread in the central area of ​​the layer, and therefore no double layer thickness in its central area when a layer width is chosen that is less than the maximum spreading width achieved by bringing together and overlapping the two subassemblies 1a, 1b.

[0053] The asphalt mix supply to the distributor is preferably controlled by its own automated system, ensuring that the asphalt mix in the cage 15 is at the minimum thickness required for proper distribution while preventing overflow. At least one sensor 18 is therefore installed within the cage to stop the supply when the asphalt mix level rises too high, risking overflow. The asphalt mix supply resumes when the level drops below the minimum required thickness. A level sensor is also installed at the outlet of each feed ramp 21, in the corresponding chute 31. Thanks to this automated system, the device can function correctly even if its settings are changed to modify the application rate of the resulting layer on the ground.

[0054] There Figure 5 allows visualization of the worm gear 20 in the cage 15 of the distributor 7 of assembly 1b. The same components are found as those described on the Figure 4 for assembly 1a and, in particular, the level sensor 18. Note the presence of a chute 31 just below the end of the feed ramp 21 and above the top opening of the cage 15, a fixed chute like the feed ramp 21 (recall that the cage 15 can move under the chute). This chute 31 forms a funnel designed to guide the bituminous mix falling from the feed ramp 21 into the cage 15.

[0055] On the Figure 6 , we can see the worm screw 20 in the cage 15 of the distributor 7 of the assembly 1a.

[0056] The function of creating a bituminous asphalt film on the conveyor belt, with a predetermined thickness between 20 mm and 100 mm plus or minus 2 mm, is performed by a guillotine-shaped leveling wall 22 of a grader. The thickness of the bituminous asphalt film is preferably at least four times the (D) of the bituminous asphalt. For example, for 0 / 10 asphalt, the film thickness under the guillotine will preferably be at least 40 mm. The height of the guillotine-shaped leveling wall 22 of the grader relative to the upper surface of the conveyor belt is adjustable to allow selection of the bituminous asphalt film thickness and thus control the amount of bituminous asphalt spread on the ground.

[0057] The function of creating the bituminous asphalt film can be associated with the transverse distribution function. It is preferable that the two conditions concerning the thicknesses of the vein in the cage and of the film on the mat be met, that is to say a vein thickness at least equal to four times the (D) of the bituminous asphalt, and a film thickness at least equal to four times the (D) of the bituminous asphalt, with modifications of these thicknesses being made in a correlated manner.

[0058] The bituminous coating film which is transported by the endless conveyor belt is then broken up by crumbling by a patterned cylinder 12 13 and then spread on the ground by falling, preferably the patterned cylinder rotating at a rotational speed such that the crumbled bituminous coating is projected onto the ground.

[0059] On the Figure 7 We can see more precisely the thread-like patterns 13 in relief, extending substantially longitudinally along the cylinder 12. They result from the welding onto the cylinder 12 of a grid of expanded metal with diamond patterns and a thickness of a few millimeters.

[0060] The embossed patterns are threadlike and essentially elongated along the length of the cylinder, forming patterns that facilitate the incorporation of the asphalt. Typically, the embossed pattern resembles a roughly regular repetition of square or diamond-shaped border shapes. Other elongated shapes are possible, such as sawtooth, triangular, chevron, or zigzag patterns, but they all have a primarily longitudinal extension along the length of the cylinder to ensure effective incorporation of the asphalt. These embossed patterns can be integrated into or applied to the surface of the cylinder.

[0061] If, ideally, the embossed patterns on the surface of the cylinder are thread-like, an alternative solution is a spiked cylinder with points and / or paddles for crumbling the film and projecting the asphalt mix onto the ground. It should be noted that the amount of asphalt projected onto the ground as a result of film crumbling can be adjusted according to requirements. The crumbled asphalt naturally falls to the ground as it is released from the endless conveyor belt, which winds downwards around the downstream inner roller and then back uphill at the bottom of the device. However, it is preferable for the patterned cylinder to rotate quickly enough so that the crumbled asphalt mix can effectively detach from the cylinder under centrifugal force. A rotation speed that is too slow for the patterned cylinder risks the formation of excessively large clumps of asphalt mix.Therefore, it is preferable for the patterned roller to rotate rapidly to project the crumbled asphalt onto the ground. In practice, the radial speed of the patterned roller is higher than the radial speed of the endless conveyor belt.

[0062] The patterned cylinder 12 13 has an effective length substantially identical to the effective width of the conveyor belt 8 and is placed at the downstream end of the endless belt 8, opposite the downstream inner roller 9. The diameter of the patterned cylinder 12 13 is at least 150 mm.

[0063] In the case of a spiked roller, the spikes are spaced approximately 10 mm apart and are 50 mm long for a 0 / 10 aggregate mix. More generally, rollers with patterns or different patterns can be used if the patterns are removable, adapted to the aggregate size of the asphalt to be sprayed. If the raised, thread-like, or spiked patterns are high enough to come into contact with the conveyor belt, these raised patterns are designed to be flexible enough to retract upon contact.

[0064] The distance between the patterned cylinder and the conveyor belt passing over the downstream inner roller opposite said patterned cylinder is adjustable by means of adjustment 23 visible on the Figure 7 The gap between the upstream and downstream inner rollers, and therefore the tension of the endless conveyor belt, is adjustable by means of adjustment means 24, which act more specifically on the position of the downstream inner roller 9. It should be noted that adjusting the position of the downstream inner roller 9 automatically moves the patterned cylinder 12 13 and the belt scraper 34, since these are mounted on a common adjustment plate. These adjustment means 23 and 24 are manually operable here, but in other embodiments, they are actuated by controlled position actuators. It is understood that these adjustments are possible at both ends of the patterned cylinder 12 13 and the extended roller 8, 9, 10 in order to maintain parallelism between the two and, for the conveyor belt, between its upstream and downstream inner rollers.

[0065] A 26-type motor, preferably hydraulic, ensures the rotation of the patterned cylinder at a speed of 200 to 400 rpm. These values ​​are given as an indication, as an order of magnitude for better understanding.

[0066] A carpet scraper 34 is positioned towards the bottom of the downstream inner roller to scrape the surface of the endless carpet in case any bituminous coating has remained stuck to the carpet and thus make it fall to the ground where it will join the rest of the bituminous coating which had been crumbled and detached from the carpet by the patterned cylinder.

[0067] On the Figure 8 The very partial overlap of the two sub-assemblies 1a and 1b is clearly visible because they are positioned to create a layer whose width corresponds to the maximum possible width, given that the distance between the two sub-assemblies is maximized. This very partial overlap is due to the fact that the effective width of the conveyor belt, and therefore of the film, is slightly less than the width of the assembly. To avoid a lack of bituminous asphalt near the center of the layer, the effective widths of the conveyors must meet the median axis of the tractor and the spreading mechanism. When a layer with a width equal to or less than the effective width of the conveyor belt is desired, only one of the two sub-assemblies is activated.

[0068] It is understood that the speeds of the different elements of the system are coordinated to prevent any interruption in supply or blockage along the path of the asphalt mix within the system. In the case of normal operation without interruption or blockage, the dosage of asphalt mix spread on the ground can be calculated using the following formula: Dosage kg / m 2 = 1000 * MVA * Ev * Vr / Va Or MVA (Mg / m 2< ) is the apparent density of the film on the endless belt, Ev (m) is the thickness of the film on the endless belt, Vr (m / min) is the speed of advancement or rotation of the belt, Va (m / min) is the speed of advancement of the device on the ground.

[0069] The apparent density of the film on the endless conveyor belt, MVA, is determined for each asphalt mix formula. The film thickness, Ev, is adjustable, and a thickness equal to four times (D) is preferably chosen, where (D) is the largest dimension of the aggregates that make up the asphalt mix formula. The forward speed or rotation speed of the endless conveyor belt and the forward speed of the device relative to the ground are synchronized and interdependent in order to obtain the desired mix proportions for the ground layer.

[0070] In one embodiment, a weighing device is installed under the section of conveyor belt located between the leveling wall and the downstream inner roller to measure the mass of the asphalt mix passing over the belt at the point of the weighing device. This device is a conveyor-weighing system, which could, for example, consist of a weighing roller extended under the belt. The weight of the asphalt mix passing over the belt can thus be continuously measured. This weighing device can be used in conjunction with the dosage calculation described above or used alone to regulate the dosage. Therefore, several methods exist for controlling the forward speed of the device on the ground and the desired dosage.

[0071] It is understood that it is therefore possible to act on one or more parameters to adjust the dosage of the bituminous coating in the ground layer, which allows for a very high degree of operational flexibility.

[0072] A control system is implemented to command and monitor the various components of the system. The operation of the spreading device can be adjusted in several ways. Generally, a target application rate (in kg / m²) for the ground layer is selected, and the control system adjusts the device's forward speed, the conveyor belt's rotation speed, and the film thickness accordingly. In some cases, one of the parameters can be constrained: for example, the device's forward speed may be imposed by an operator, and the control system will then adjust the other two parameters. It should be noted that the control system may include tables or calculation formulas that provide ranges of possible parameter values ​​based on the application rates. It is then possible to implement safety mechanisms that inform the operator if the desired application rate cannot be achieved.For example, if the operator sets a spreading speed that is too high for a given mix design and desired application rate, the system will indicate that this is not possible and may suggest a lower, compatible spreading speed. Furthermore, based on the desired application rate, the system can determine an optimal spreading speed in terms of consumption and / or project time, or any other optimization criteria, such as the speed or rotation period of the semi-trailers supplying the asphalt mix to the machine equipped with the spreading device.

[0073] Similarly, the automated system can, thanks to sensors, take into account certain deformations of the ground on which the layer is to be laid. Thus, the application rate at the xy coordinates can be made proportional to the z-shaped deformation of the pavement. The z-values ​​as a function of the xy coordinates can be predefined and used for controlling the automated system or measured in real time. In this mode, the operator can optionally define maximum and minimum application rates.

[0074] On the Figure 9 The paving tractor can be seen in action, spreading a layer 4 of asphalt. It can be noted that assembly 1a is higher and further back than assembly 1b. This rearward position of the upper assembly 1a is due to the fact that its feed ramp 21 is longer and has the same incline as the shorter ramp of the lower assembly 1b. A film of asphalt is laid across the entire effective width of each belt 8, and this film is broken up by the corresponding patterned roller 12 to form crushed asphalt 5, which lands on the ground to form layer 4. It can be noted that the resulting layer 4 is relatively thin, a thickness that would be difficult to achieve with a conventional paver.

[0075] Two-cylinder rough spreading devices are schematically shown on the Figure 10 with a side view in section of a 100 rolling and crumbling sub-assembly according to an alternative to the invention.

[0076] In this cross-section, a hopper 102 has, on the upstream side for introducing the asphalt mix, a distributor 7, and on the downstream side for exiting the crumbled, rolled asphalt mix 5, two rough rollers 112 which ensure the rolling of the distributed asphalt mix and then the crumbling of the resulting asphalt film. In this embodiment, the crumbling occurs almost immediately after rolling. The feed function 11 is represented by an enlarged arrow, but in a variant, the hopper 102, instead of being a simple hopper for introducing asphalt mix 101 from a storage unit further upstream, can also be a storage unit for the asphalt mix.In the latter case, it may be advantageous for the storage means of the hopper 102 to be slightly offset from the vertical of the outlet of the crumbly rolled bituminous mix 5 so that the variable weight of the column of stored bituminous mix whose height can vary has little influence on the dosage of the bituminous mix at the outlet, this offset may correspond to a bend or a drop inclined towards the distributor 7 and the two rough cylinders 112.

[0077] There Figure 11 This schematically represents a roller trailer 114 attached to a spreading device according to the invention, for example, the one with the rolling and crumbling sub-assembly described above. This trailer, in addition to its capacity to store a bonding / sealing emulsion, allows, after the spreading of the bituminous asphalt layer on the ground, the compaction of said layer. The trailer 114 includes rollers 115 that allow the machine to move on layer 4. The trailer 114 includes a compartmentalized 6 m3 tank 116 with a first section for a bonding / sealing emulsion and a second section for water intended for spraying the rollers 114. These rollers 115 are shown as three in number, but it is understood that this number and / or the rolling structure of the machine can be adapted according to the needs, as can the length of each roller, which here is 1.50 m and has a smooth rim.Trailer 114 also includes a platform with a pump for the bonding / sealing emulsion, a pump for watering the rollers, and an air compressor for forming jets of bonding / sealing emulsion from boom 19. The trailer can also be equipped with a generator.

[0078] A spray bar 19 for applying a layer 3 of bonding emulsion to the ground 2 and a spreading sub-assembly are schematically represented at the front of the trailer 114, according to the direction of travel 32 of the assembly. The bonding / sealing emulsion and compressed air are transmitted to the spray bar 19 by hoses schematically represented on the Figure 11(dotted line). Behind ramp 19 is the two-roller roughening / rolling sub-assembly 100, which deposits crumbled asphalt 5 onto the ground, possibly by projecting it, and lays the asphalt layer 4 on the ground 2. The trailer's rollers operate further back to compact the laid asphalt layer 4. Connecting means 117 connect the trailer 114 to the spreading machine, which includes the spreading sub-assembly(ies).

Claims

1. A device for spreading a layer (4) of a bituminous coated material onto a ground (2) to be covered, including means for moving on said ground in a longitudinal direction of advance (32) and spreading means supplied with bituminous coated material by supply means and adapted to spread during the displacement of the device the layer of bituminous coated material over a determined width of said ground, considered transversally to the direction of advance, the spreading means being adapted to perform above the ground a rolling of the bituminous coated material and a crumbling of the rolled bituminous coated material and the fall towards the ground of the crumbled bituminous coated material, characterized in that the spreading means include at least one crumbling rolling sub-unit consisted of an extended roll and a rough cylinder and in that the extended roll is formed by an end part of an endless conveyer belt (8) extended between an upstream inner roll (10) and a downstream inner roll (9), the upstream and downstream inner rolls being parallel to the rough cylinder (12), the downstream inner roll (9) being opposite to the cylinder (12), the belt (8) having a width substantially equal to the length of the cylinder, a film (6) of determined thickness (e) of bituminous coated material being made on the upper surface of the belt (8), said film being driven towards the cylinder by said belt, the determined distance between the surfaces of the cylinder and of the belt passing on the downstream inner roll being lower than the determined thickness (e) of the film (6) of bituminous coated material made on the upper surface of the belt (8).

2. The device according to claim 1, characterized in that the spreading means are adapted to perform the spraying of the crumbled bituminous coated material, in order to it to fall towards the ground.

3. The device according to claim 2, characterized in that the cylinder turns, in absolute value, at a higher speed than the radial speed of the belt (8) passing on the downstream inner roll (9).

4. The device according to claim 1, 2 or 3, characterized in that it includes a distributor adapted to spread out the bituminous coated material at the entrance of the spreading means.

5. The device according to one of the preceding claims, characterized in that the film (6) of determined thickness (e) of bituminous coated material is made on the upper surface of the belt (8) by a grader arranged on the upstream side of said belt.

6. The device according to claim 5, characterized in that the grader includes a transverse grading wall (22), whose lower end is substantially parallel to the upper surface of the belt (8) and whose grader end is at an adjustable determined height relative to the upper surface of the belt.

7. The device according to one of claims 5 and 6, characterized in that the section of the belt (8) arranged between the grading wall (22) and the downstream inner roll (9) is equipped with a weighting belt system that allows measuring the mass of the vein of coated material that passes on the belt at said weighting belt system.

8. The device according to one the preceding claims, taken in dependence on claims 4 and 5, characterized in that the distributor (7) is arranged transversally above the belt (8) and upstream from the grading wall (22), the distributor (7) being adapted to spread bituminous coated material, upstream from the grading wall, over a determined width of the belt and over a height higher than the determined thickness (e) of the film (6) of bituminous coated material to be made.

9. The device according to one the preceding claims, taken in dependence on claim 4, characterized in that the distributor (7) includes, in a cage (15), an endless screw (20) for driving the bituminous coated material over the width of the belt (8), the cage, closed by lateral walls, having no bottom so that the bituminous coated material can be distributed over the upper surface of the belt, and being open at the top for the supply (11) with bituminous coated material.

10. The device according to claim 9, taken in dependence on claims 4 and 5, characterized in that the grading wall (22) forms the downstream lateral wall of the cage (15) of the distributor (7), the cage of the distributor being located at an adjustable determined height relative to the upper surface of the belt.

11. The device according to any one the preceding claims, characterized in that it includes a carrier frame (16) of two crumbling rolling sub-units (1a, 1b) each consisted of a rough cylinder (12) and an extended roll (8, 9, 10), the two sub-units (1a, 1b) being offset, on the one hand, laterally relative to each other and, on the other hand, in height relative to each other, the two sub-units being laterally mobile in translation against the carrier frame so as to be able to move the two sub-units apart from each other or closer to each other in overlapping in a lateral direction parallel to the width of the path and hence to increase or reduce the determined width of said ground onto which the bituminous coated material is spread.

12. The device according to claim 11, taken in dependence on claim 4, characterized in that it includes one distributor (7) per crumbling rolling sub-unit, the two distributors of the two crumbling rolling sub-units transporting the bituminous coated material in two diverging opposite directions over a width of each endless belt, and in that the distributor is supplied with bituminous coated material through a chute (31) in fixed position above the cage (15) of the distributor (7), and in that the two chutes (31) for the two crumbling rolling sub-units (1a, 1b) are arranged against the median axis of the device superimposable to the direction of advance (32).

13. The device according to any one of the preceding claims, characterized in that it forms a self-propelled spreading machine, said spreading means being arranged on the rear of said machine, or being removably installed on the rear of a self-propelled machine (14), said self-propelled machine including from the front / upstream to the rear / downstream according to the direction of advance: a reserve (35) of bituminous coated material, at least one line (30) for conveying the bituminous coated material towards the rear and said spreading means.

14. The device according to any one of the preceding claims, characterized in that relief patterns (13) are substantially elongated over the length of the cylinder.

15. The device according to claim 14, characterized in that the relief patterns (13) are substantially filiform and of a height comprised between 1 mm and 15 mm.

16. A method for spreading a layer (4) of a bituminous coated material onto a ground (2) to be covered, wherein, at a first time, the bituminous coated material is rolled to form a film (6) of determined thickness (e) of bituminous coated material over a determined width and at a certain distance above the ground and, at a second time, said film is crumbled (5) and the bituminous coated material of the crumbled film is made fall onto the ground, characterized in that the film of determined thickness (e) of bituminous coated material is made over an upstream part of an extended roll (8, 9, 10) consisted of an endless conveyor belt (8) extended between an upstream inner roll (10) and a downstream inner roll (9), and in that a cylinder (12) including relief patterns (13) opposite to the downstream inner roll to crumble (5) the film (6) made on the endless belt (8) is implemented.

17. The method according to claim 16, characterized in that it is implemented a bituminous coated material chosen among: a hot coated material of fabrication temperature higher than 150°C, a lukewarm coated material of fabrication temperature higher than 100°C and lower than 150°C, a half-lukewarm coated material of fabrication temperature comprised between 85°C and 100°C, a half-cold or cold coated material of fabrication temperature lower than 85°C.

18. The method according to one of claims 16 and 17, characterized in that it is implemented a bituminous coated material whose values d and D of the d / D ratio are chosen among: a value of 0-2-4 or 6.3 mm for d and a value of 4-6.3-10-14-20 mm for D.